Fluctuating Population Dynamics Promotes the Evolution of Phenotypic Plasticity
Authored by Michael Doebeli, Richard Svanback, Mario Pineda-Krch
Date Published: 2009
DOI: 10.1086/600112
Sponsors:
National Science and Engineering Research Council of Canada (NSERC)
Swedish Foundation for Strategic Research (PH)
James S. McDonnell Foundation
Swedish Research Council
Platforms:
No platforms listed
Model Documentation:
Other Narrative
Flow charts
Model Code URLs:
Model code not found
Abstract
Theoretical and empirical studies are showing evidence in support of
evolutionary branching and sympatric speciation due to
frequency-dependent competition. However, phenotypic diversification due
to underlying genetic diversification is only one possible evolutionary
response to disruptive selection. Another potentially general response
is phenotypic diversification in the form of phenotypic plasticity. It
has been suggested that genetic variation is favored in stable
environments, whereas phenotypic plasticity is favored in unstable and
fluctuating environments. We investigate the ``competition{''} between
the processes of evolutionary branching and the evolution of phenotypic
plasticity in a predator-prey model that allows both processes to occur.
In this model, environmental fluctuations can be caused by complicated
population dynamics. We found that the evolution of phenotypic
plasticity was generally more likely than evolutionary branching when
the ecological dynamics exhibited pronounced predator-prey cycles, whereas the opposite was true when the ecological dynamics was more
stable. At intermediate levels of density cycling, trimorphisms with two
specialist branches and a phenotypically plastic generalist branch
sometimes occurred. Our theoretical results suggest that ecological
dynamics and evolutionary dynamics can often be tightly linked and that
an explicit consideration of population dynamics may be essential to
explain the evolutionary dynamics of diversification in natural
populations.
Tags
long-term
sympatric speciation
Individual specialization
Eurasian perch
Dependent disruptive selection
Size-structured populations
Salvelinus-alpinus
Arctic charr
Ecological specialization
Resource polymorphism